Fluidic gaging device

ABSTRACT

A fluidic gage having no moving mechanical parts is utilized for continuous monitoring of a particular parameter such as wire diameter, sliver density and object proximity. The gage comprises a bridge circuit including a pair of fluidic resistors having fixed resistances to fluid flow therethrough and a first fluidic variable resistor in three legs of the bridge circuit. A sensing head is connected in the fourth leg of the bridge circuit in fluid communication with the monitored material to function as a second fluidic variable resistor. The first variable resistor is preset to a predetermined resistance value corresponding to a desired value of the monitored parameter. Deviation from the desired value of the monitored parameter causes a linear change in fluid pressure at the input to the sensing head thereby causing an unbalanced condition of the bridge circuit and developing a pressurized fluid signal which may be utilized for operating a suitable readout device or initiating a control action.

United States Patent [73 Inventor James L. Reimers 3.469.988 9il969Yttwger. i. 99/362XR WI \0 i lz FOREIGN PATENT m I970 hoLZII |2/|95|Great Britain m/m [45 P n d 6. 97 809.651) 2/1959 UI'CHI Britain t t 4 il l 34/]30 I731 \ssignee FMC Corporation San Jose (jam: PrimaryExuminer- Robert l.. Bleutge :Hmrmqu F. W. Anderson and (I Tripp I54]COOKERCARRIERS wk Wm 10 C|aim 4l)r win Fi ABSTRACT: Carriers for ahydrostatic cooker conveyor 34/12,, each formed from three elongatedangle bars connected together by a thin membrane tie member. Flat sidesof two I I in CI M 3/04, of the angle bars are welded to the membrane toform a wide T-shaped retaining member while the apex of the third angle(0| Field of Search 13 bar is welded to the membrane and faces the otherangle 36' U043: bars to define a V-shaped retaining member. Mounting m mplates are welded to each end of the angle bars and memlqbl Referencescited brane and are attached to endless chains to define a processingconveyor. The angle bars. mounting plates. and UNITED STATES PATENTSmembrane cooperate to suppon containers being heat 2,528,069 10/1950McGihon l34/130XR treated and also serve as a trough for capturing asupply 2.667,88l 2/1954 Watkins etal I34/l3l of cooling water andcontrolling its discharge upon con- 3.347.35I 10/1967 Mencacciet all98/i3l tainers supported in other carriers therebelow by vinure of3.394.793 7/l968 Reimers et al... l9S/l3l spaced drain holes formed inthe membrane.

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fmav m COOKER CARRIERS BACKGROUND Ol- THE INVENTION l-ield oftheIntention This invention relates to the cooking art and moreparticularly relates to improvements to carriers for hydrostaticcookers.

Description of Prior Art The cooker carrier bars of the presentinvention are an improvement over those disclosed in my United StatesPatent No. 3.452.858 which issued on July I. I969. In my prior artdevice aT-shaped retaining flange and a Vshaped retaining flange areconnected together by narrow tie members which are disposed at spacedintervals such as at two foot intervals. When the containers beingprocessed were cans. it was determined that these tie members wouldcontact and dent the cylindrical surfaces of the cans. It was alsodetermined that cooling water was not effectively used by these priorart carriers since a large amount of the water that entered one carrierwould not gravitate downwardly against the containers and the carrierstherebelow but would be guided outwardly of these carriers by thedownwardly and outwardly angled portions of the V-shaped retainingflanges.

Carriers of the type disclosed in my United States Patent No. 3.394.793which issued on July 30. I968 are also some what pertinent. This patentdiscloses one-piece I-beam carriers each provided with holes in its web.These carriers. however. include a flat generally horizontal cansupporting surface. when the carriers are moved along a vertical path.having loosely fitted end plates thereon. Because of the loose fit ofthe end plates and because the containers are disposed over the holes inthe flat web of the carriers thereby resisting flow of water toward theholes. the water tends to seek the lowest area in each carrier. The lowarea of each carrier is usually found at one of its corners.Accordingly. a considerable amount of water in the carrier flows alongone of the can retaining flanges and is discharged from the carrierspast the associated loosely fitted end plate. This discharged water.therefore. is not directed against the containers in cam'erstherebetween and its cooling potential is wasted.

SUMMARY OF THE INVENTION The carriers of the present invention includeangle bars that are connected together to define an elongated T-shapedretaining member having a thick normally horizontal flange or web and anelongated V-shaped retaining member. A membrane extends the full lengthof and is welded to the T-shaped member and to the apex of the V-shapedmember thus allowing only the beads or chimes of cans to contact thecarriers. Water retaining end plates are welded to each end of thecarriers thereby making each cam'er a stepped water collecting troughwith the lower step or water pocket being defined between the inner edgeof the thick horizontal web and the apex of the \'-shaped member. Themembrane is provided with a plurality of drain holes which control thedischarge of cooling water downwardly from one carrier onto thecontainers of the next lower carrier thereby more effectively using thecooling water. The containers in each carrier also serve to restrict thedrain holes thereby maintaining a supply of water in the lower portionor water pocket of each carrier for a longer period than was heretoforepossible thus improving the cooling efficiency of the cooker.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a diagrammatic verticalcentral section of a hydrostatic cooker through which the carriers ofthepresent invention are moved.

FIG. 2 is an enlarged diagrammatic operational view in vertical sectiontaken through two of the carriers when moving downwardly in the coolingzone at the point indicated by the arrow 2 in FIG. I. the supportingconveyor chain being omitted from this view for clarity and certain ofthe carriers being illustrated with two different sizes of containerstherein.

FIG. 3 is a section taken at a reduced scale and along lines 3-3 of FIG.2 illustrating the manner in which the containers restrict the flow ofliquid through the drain holes.

FIG. 4 is an enlarged perspective looking in the direction of arrows 4-4of FIG. 1 illustrating several of the carriers connected to two parallelendless chains of a processing conveyor. the central portion of thecarriers being cut away.

DESCRIPTION OF PREFERRED EMBODIMENT The carriers [0 (FIGS. 2 and 3) ofthe present invention are adapted to handle rows of containers C. whichrows are about 7 feet long. Although the containers C are illustrated asfilled and sealed cans having chimes ll (FIG. 3) around their ends, itwill be understood that other types of containers. such as glass jars orcapsules. may be handled in the carriers Ill. The carriers 10 form apart of an endless processing conveyor 12 of a hydrostatic cooker 14(FIG. I).

The hydrostatic cooker [4 comprises a pair of spaced vertical walls 16(only one being shown). A housing [8 of generally inverted U-shapedconfiguration is secured to the walls 16 and defines a steam chamber 19filled with steam at a high temperature and at a superatmosphericpressure. A water filled inlet hydrostatic leg 20 is defined by walls22, 23 and a floor 24: and a discharge or cooling hydrostatic leg 26 isdefined by walls 28, 30 and a part of the floor 24. The walls 22, 23, 28and 30 and the floor 24 are all secured in fluid tight engagement to thewalls 16 and communicate therewith by virtue of a trough 32 defined inthe lower portion of the cooker 14. Steam at about 250 F and I5 p.s.i.g.is directed into the steam chamber. and is balanced by a column of warmwater in the inlet hydrostatic leg 20. and a column of cool water in thedischarge hydrostatic leg 26.

In addition to the cooling performed by the outlet leg 26. the conveyorI2 moves the containers C through an atmos pheric cooling zone 34 duringwhich time cooling water from manifolds 36 is sprayed onto thecontainers C and into the carriers 10 through several series of sprayheaders 38 each of which includes distributing means such as troughs ornozzles 40 which are spaced apart and extend the full length of thecarriers 10. A cooling housing 42 is defined by a floor 44 and walls 46,47 and 48 which are secured to walls 16 so as to collect the coolingwater and discharge or recirculate the same by means of valved conduits50.

The conveyor 12 includes a pair of spaced chains 52 and 54 (FIG. 4)trained around a plurality of pairs of sprockets 56 (FIG. I) keyed toshafts 58 journaled in the upper portion of the cooker 14. The chains 52and 54 each include a series of pivotally interconnected inner links 58(FIG. 4) and outer links 60. The chains are guided through the cooker bythe sprockets 56 and guide tracks (not shown) and are continuouslydriven in the direction of the arrows by a motor 61 (FIG. I) that isconnected to at least one of the shafts 58 by a chain drive 62. Thechains 52 and 54 are also trained around a pair of small diametersprockets 63 at a feed station FS and discharge station D5 which opensthe carriers sufficiently to receive and discharge rows of containers.

A feed mechanism 64 of well known design is provided for deflecting rowsof con ainers into the carriers at the feed statipr ES, and afle r theserows of containers have moved tliEnigh the coo Er and through'the'cooling zone 34, the processed and cooled containers are dischargedonto a discharge conveyor66 at the discharge station DS.

As illustrated in FIGS. 2 and 4. each carrier 10 includes a pair ofelongated angle bars 70 having two adjacent generally horizontal flangeswhich cooperate to define .t web 72 that has an elongated portion of amembrane 74 welded there between. [he angle bars 70 defines al-\httPLt.l retaining member 76 which include a tertical containerretaining ide plate. The membrane 74 has .i plurality of drain holes 77therein disposed in \ertical alignment with the longitudinal .nes of thecontainers when the conseyor 121s moving along a vertical path asindicated in l*'l(|v 2.

The apex 78 of another angle member 80 is welded to the other elongatededge of the membrane 74 and defines a Vshaped retaining member 82. Oneend of the T-shaped retaining member 76. one end of the \"-shaped member82. and one end of the membrane 74 are each welded to a narrow end plate84 which is bolted to the inner wall 86 of the as sociated inner link 59of one of the chains 52 or 54. The other end of the T-shaped member 76.\'-shaped member 82 and membrane 74 is welded to a wider end plate 90which end plate is bolted to an outer wall 92 of the associated widelink 60 of the other chains 52 or 54. The T-shaped retaining member 76.V-shaped retaining member 82. apertured membrane 74 and end plates 84and 90 cooperate to define a stepped trough 93. The trough includes alower nan'ow portion or water pocket 94 disposed inwardly of the web 72of the T-shaped retaining member 76. and a wide portion 95 which extendsto the upstanding flange of the T-shaped retaining member 76 asillustrated in FIG. 2. Thus. if the supply of cooling water is low. thecooling water will be concentrated within the narrow portion 94 of thetrough 93 to more effectively cool the containers. The specificconstruction of the endless chains 52 and 54 is identical to thatdisclosed in my above mentioned patent and accordingly will not bedescribed in further detail herein.

A feature of the invention is that when cylindrical containers are beingprocessed the cylindrical surfaces of the containers are disposed closeto the drain holes 77 and serve to restrict the flow of cooling liquidout of the carriers as indicated in FIGS. 2 and 3. thus prolonging thecooling effect on the lower portion of the containers which remainsubmerged in the cooling water for an appreciable period. Since the flowof water through the drain holes is restricted as above mentioned. thepressure is reduced allowing the water to spread more evenly over thesmall containers C or large containers C disposed therebelow asindicated in FIGS. 2 and 3.

In operation. rows of containers are deflected into the carriers l0 atthe feed station FS. If the containers being processed are filled andsealed cans. the chimes ll of the cans move into the carriers 10 andonto the membrane 74. Because the membrane extends the full length ofthecarriers. the only part of the containers C which contact the carriersit! are the chimes l1 and. accordingly. the easily dented cylindricalbody portion of the containers between the chimes are not damaged.

Also. because the membranes 74 is quite thin. being on the order of 1,of an inch in thickness. slightly larger containers such as thecontainers C (FIG. 2) can be accommodated therebetween than would bepossible if the carriers had a thick web.

After the rows of containers have been sterilized by being moved throughthe inlet hydrostatic leg 22. sterilizing chamber 19. and the coolinghydrostatic leg 26. the containers are moved into the atmosphericcooling zone 34. While in this cooling zone. water is discharged ontothe containers C and into the carriers 10 as the carriers move past thenozzles 40 on each of the headers 38. As indicated in FIGS. 2 and 3.each carrier defines a stepped trough which collects the cooling waterand controls the discharge of the water by directing it into the waterpocket 94 and then downwardly through the hole 77 in the membrane 74against the containers in the next lower carrier [0. The water followsthe curved surface of the containers and is collected in each carrier inturn for discharge upon the containers therebelow. In this way. thecooling efl'tciency is greatly imporved.

From the foregoing description it is apparent that by \irtuc of acontinuous membrane which extends from one end to the other end of theelongated carriers of the present imention. the carriers precludedenting of the cylindrical urfaces of the containers. Since the membraneis quite thin. larger containers may be accommodated between thecarriers than w as heretofore possible. The carriers also define astepped trough within which cooling water collects and is controllablydischarged through drain holes therein onto containers therebelow forcollection in these troughs thereby greatly improving the coolingefficiency ofthe cooker.

Although the best mode contemplated for carrying out the presentinvention has been herein shown and described. it will be apparent thatmodification and variation may be made without departing from what isregarded to be the subject matter ofthe invention.

What I claim is:

1. In a conveyor for a hydrostatic cooker ofthe type having a pair ofspaced endless chains guided along a circuitous path having verticalruns moving through a heat treatment zone wherein water is directed ontothe conveyor. each chain being formed by a plurality of narrow and widelinks pivotally connected together. and elongated container supportingcarriers connected to and extending between the chains. said carrierseach comprising a normally vertical side plate retaining member on oneside. a V-shaped side plate retaining member on the other side. mountingplates secured to the ends of said members. and a container supportingmembrane at the horizontal mid plane of said members; the improvementwherein said container supporting membrane tightly connects to both sidemembers and to both mounting plates. and relatively thick flange meansprojecting inwardly from said normally vertical side plate retainingmember and stopping short of the mid plane of said membrane for cooperating with said V-shaped side plate member to form a relativelynarrow water pocket. said membrane having a plurality of drain holessubstantially centered between the ends of said flange means and theapex of said V-shaped side plate member for bleeding water past thewalls of the containers supported on said membrane and out of said waterpocket.

2. An apparatus according to claim 1 wherein said normally vertical sideplate retaining members and said relatively thick flange means comprisesa pair of angle bars secured to said membrane on opposite sides of saidmid plane and wherein one flange of each angle bar lies in a commonvertical plane when the conveyor is moving along a vertical run.

3. la a conveyor for a hydrostatic cooker ofthe type having a pair ofspaced endless chains guided along a circuitous path having verticalruns moving through a heat treatment zone wherein water is directed ontothe conveyor. each chain being formed by a plurality of narrow and widelinks pivotally connected together. and elongated container supportingcarriers connected to and extending between said chains: the improvementwherein said carriers each comprise means defining an elongated T-shapedretaining member including a normally horizontal web: a V-shapedretaining member having an apex which is spaced from said web; mountingplates secured to the ends of said T-shaped member and said V-shapedmember and being rigidly secured to as .sociated links on the adjacentsupporting chains: each of said mounting plates being wider than thethickness of said web; and a membrane connected in liquid tightengagement to said web. apex and mounting plates whereby water directedinto said carriers is collected therein: said membrane having aplurality of drain holes therein arranged to direct the collected waterdownwardly onto containers in carriers therebelow; said T-shaped member.said V-shaped member. said membrane and said mounting plates cooperatingto define a stepped trough having a narrow step that is partiallydefined by the inner edge of said web and the apex of said V-shapedmember.

4. An apparatus according to claim 3 wherein said T- shaped member andsaid web are fabricated from a portion of said membrane and from a pairof angle bars having parallel innardl directed flanges tightly fitted onopposite sides of said portion of said membrane.

8. An apparatus according to claim 3 wherein the drain holes and thelongitudinal axes of the containers supported by adjacent carriers whenmoving through said vertical runs lie in a common plane. wherein thecontainers are cylindrical cans with chimes on both ends. and whereinthe space be tween the membrane and the lower cylindrical surface ofeach can serves to restrict the flow of water through the drainopenings.

9. An apparatus according to claim 3 wherein the T-shaped retainingmember is formed by two angle bars tightly secured to the mountingplates and to said membrane.

l0. An apparatus according to claim 9 wherein the V- shaped retainingmember is an angle bar having its apex welded to the membrane.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.5,590,8Q1 Dated February 25, 1976 Invent James L. Reimers It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

On the Cover Sheet the illustrative figure should appear as shown.

Signed and Sealed this Fourteenth D ay Of September 1976 [SEAL] Arrest.-

RUTH C. MASON C. MARSHALL DANN Allesring Officer Commissioner uj'Paremsand Trademarks

1. A fluidic gage having no moving mechanical parts for continuousmonitoring of a particular parameter such as wire diameter, sliverdensity, object proximity and the like, comprising a pair of fluidicresistors having fixed resistances to fluid flow therethrough, firstfluidic resistor means having selected variable resistance to fluid flowtherethrough, a first sensing head provided with at least one inputfluid flow passage and output end means adapted to be in close proximityand in fluid communication with a selected material having a particularparameter being continuously monitored by said gage whereby said firstsensing head functions as a second fluidic resistor having a resistanceto fluid flow therethrough which is variable as a function of the valueof the monitored parameter, said pair of fixed resistors, first variableresistor means and first sensing head connected in bridge circuitrelationship, the bridge circuit connected to a source of pressurizedfluid, the resIstance of said first variable resistor means preset to aselected resistance corresponding to the desired value of the monitoredparameter to obtain a balanced condition of the bridge circuit when themonitored parameter of the material passing in close proximity to and influid communication with said first sensing head is at the desired valuethereof, the bridge circuit developing a pressurized fluid signal duringthe unbalanced conditions of the bridge circuit when the value of themonitored parameter deviates from the desired value, said pair of fixedresistors having first ends thereof connected to a first juncture of thebridge circuit, the source of pressurized fluid connected to said firstjuncture, an input end of said at least one input fluid flow passage ofsaid first sensing head and a second end of a first of said pair offixed resistors connected to a second juncture of the bridge circuit,said pair of fixed resistors further comprising a single laminatedstructure of small dimension and each fixed restrictor being a longcapillary passage of predetermined length, the resistance values of eachof the pair of fixed resistors are equal, the laminated restrictorstructure rendering said gage a portable device.
 2. A fluidic gagehaving no moving mechanical parts for continuous monitoring of aparticular parameter such as wire diameter, sliver density, objectproximity and the like, comprising a pair of fluidic resistors havingfixed resistances to fluid flow therethrough, first fluidic resistormeans having selected variable resistance to fluid flow therethrough, afirst sensing head provided with at least one input fluid flow passageand output end means adapted to be in close proximity and in fluidcommunication with a selected material having a particular parameterbeing continuously monitored by said gage whereby said first sensinghead functions as a second fluidic resistor having a resistance to fluidflow therethrough which is variable as a function of the value of themonitored parameter, said pair of fixed resistors, first variableresistor means and first sensing head connected in bridge circuitrelationship, the bridge circuit connected to a source of pressurizedfluid, the resistance of said first variable resistor means preset to aselected resistance corresponding to the desired value of the monitoredparameter to obtain a balanced condition of the bridge circuit when themonitored parameter of the material passing in close proximity to and influid communication with said first sensing head is at the desired valuethereof, the bridge circuit developing a pressurized fluid signal duringthe unbalanced conditions of the bridge circuit when the value of themonitored parameter deviates from the desired value, said pair of fixedresistors having first ends thereof connected to a first juncture of thebridge circuit, the source of pressurized fluid connected to said firstjuncture, an input end of said at least one input fluid flow passage ofsaid first sensing head and a second end of a first of said pair offixed resistors connected to a second juncture of the bridge circuit,said pair of fixed resistors further comprising a single laminatedstructure of small dimension and each fixed resistor being a longcapillary passage of predetermined length, the resistance values of thepair of fixed resistors are unequal, the laminated resistor structurerendering said gage a portable device.
 3. A fluidic gage having nomoving mechanical parts for continuous monitoring of a particularparameter such as wire diameter, sliver density, object proximity andthe like, comprising a pair of fluidic resistors having fixedresistances to fluid flow therethrough, first fluidic resistor meanshaving selected variable resistance to fluid flow therethrough, a firstsensing head provided with at least one input fluid flow passage andoutput end means adapted to be in close proximity and in fluidcommunication with a selected material having a particular parameterbeing continuously monitored by said gage whereby said first sensinghead functions as a second fluidic resistor having a resistance to fluidflow therethrough which is variable as a function of the value of themonitored parameter, said pair of fixed resistors, first variableresistor means and first sensing head connected in bridge circuitrelationship, the bridge circuit connected to a source of pressurizedfluid, the resistance of said first variable resistor means preset to aselected resistance corresponding to the desired value of the monitoredparameter to obtain a balanced condition of the bridge circuit when themonitored parameter of the material passing in close proximity to and influid communication with said first sensing head is at the desired valuethereof, the bridge circuit developing a pressurized fluid signal duringthe unbalanced conditions of the bridge circuit when the value of themonitored parameter deviates from the desired value, said first variableresistor means comprises a second sensing head operatively identical tosaid first sensing head and adapted to be in close proximity andretained in fluid communication with a fixed portion of the selectedmaterial having the desired value of the monitored parameter wherebysaid second sensing head functions as a reference resistance to fluidflow therethrough corresponding to the desired value of the monitoredparameter.
 4. A fluidic gage having no moving mechanical parts forcontinuous monitoring of a particular parameter such as wire diameter,sliver density, object proximity and the like comprising a pair offluidic resistors having fixed resistances to fluid flow therethrough,first fluidic resistor means having selected variable resistance tofluid flow therethrough, a first sensing head provided with at least oneinput fluid flow passage and output end means adapted to be in closeproximity and in fluid communication with a selected material having aparticular parameter being continuously monitored by said gage wherebysaid first sensing head functions as a second fluidic resistor having aresistance to fluid flow therethrough which is variable as a function ofthe value of the monitored parameter, said pair of fixed resistors,first variable resistor means and first sensing head connected in bridgecircuit relationship, the bridge circuit connected to a source ofpressurized fluid, the resistance of said first variable resistor meanspreset to a selected resistance corresponding to the desired value ofthe monitored parameter to obtain a balanced condition of the bridgecircuit when the monitored parameter of the material passing in closeproximity to and in fluid communication with said first sensing head isat the desired value thereof, the bridge circuit developing apressurized fluid signal during the unbalanced conditions of the bridgecircuit when the value of the monitored parameter deviates from thedesired value, said pair of fixed resistors having first ends thereofconnected to a first juncture of the bridge circuit, the source ofpressurized fluid connected to said first juncture, an input end of saidat least one input fluid flow passage of said first sensing head and asecond end of a first of said pair of fixed resistors connected to asecond juncture of the bridge circuit, said first sensing headcomprising a body having a cylindrical hollow interior forming saidinput fluid flow passage, a first end of the body being the input end ofsaid input fluid flow passage supplied with pressurized fluid from thesecond juncture of the bridge circuit, a second end of the body beingthe output end means spaced a predetermined distance from the surface ofa material whose proximity to the second end of the body is beingmeasured, the second end of the body having a curved surface conformingto the curved surface of the material being monitored wherein thematerial is A cylindrical or spherical shape whereby the gage functionsas an out-of-roundness gage determining the out-of-roundness of thecylindrical or spherical shaped material, and a predetermined resistancevalue of said first variable resistor determining a desired proximitydistance between the second end of the body and the material beingmonitored whereby any deviation in the spacing thereof from the desiredvalue causes an unbalanced pressure condition in the bridge circuit anddevelops a pressurized fluid signal indicative thereof.
 5. A fluidicgage having no moving mechanical parts for continuous monitoring of aparticular parameter such as wire diameter, sliver density, objectproximity and the like, comprising a pair of fluidic resistors havingfixed resistances to fluid flow therethrough, first fluidic resistormeans having selected variable resistance to fluid flow therethrough, afirst sensing head provided with at least one input fluid flow passageand output end means adapted to be in close proximity and in fluidcommunication with a selected material having a particular parameterbeing continuously monitored by said gage whereby said first sensinghead functions as a second fluidic resistor having a resistance to fluidflow therethrough which is variable as a function of the value of themonitored parameter, said pair of fixed resistors, first variableresistor means and first sensing head connected in bridge circuitrelationship, the bridge circuit connected to a source of pressurizedfluid, the resistance of said first variable resistor means preset to aselected resistance corresponding to the desired value of the monitoredparameter to obtain a balanced condition of the bridge circuit when themonitored parameter of the material passing in close proximity to and influid communication with said first sensing head is at the desired valuethereof, the bridge circuit developing a pressurized fluid signal duringthe unbalanced conditions of the bridge circuit when the value of themonitored parameter deviates from the desired value, said pair of fixedresistors having first ends thereof connected to a first juncture of thebridge circuit, the source of pressurized fluid connected to said firstjuncture, an input end of said at least one input fluid flow passage ofsaid first sensing head and a second end of a first of said pair offixed resistors connected to a second juncture of the bridge circuit,said first sensing head comprising a relatively long nonflexible tubinghaving a length equal to at least three times the inner diameter thereofand forming said output end means, the tubing providing a passage for alow-density fibrous material being monitored by said gage and having adiameter greater than the inner diameter of said tubing whereby thematerial is compressed in its passage therethrough, and said at leastone input fluid flow passage comprising a pair of passages supplied atthe input ends thereof with pressurized fluid from the second junctureof the bridge circuit and the output ends thereof in communication withthe interior of said tubing in diametrically opposed relationship at aregion spaced equally from the ends thereof whereby the pressurizedfluid issuing into the interior of said tubing from said pair ofpassages escapes through the ends of said tubing, said tubing andmaterial passing therethrough forming a variable constriction to fluidflow due to the variable density of the material, the variableconstriction forming variable resistance to fluid flow therethrough andcausing the fluid pressure at the second juncture of the bridge circuitto vary directly with the density of the monitored material.
 6. Afluidic gage having no moving mechanical parts for continuous monitoringof a particular parameter such as wire diameter, sliver density, objectproximity and the like, comprising a pair of fluidic resistors havingfixed resistances to fluid flow therethrough, first fluidic resistorMeans having selected variable resistance to fluid flow therethrough, afirst sensing head provided with at least one input fluid flow passageand output end means adapted to be in close proximity and in fluidcommunication with a selected material having a particular parameterbeing continuously monitored by said gage whereby said first sensinghead functions as a second fluidic resistor having a resistance to fluidflow therethrough which is variable as a function of the value of themonitored parameter, said pair of fixed resistors, first variableresistor means and first sensing head connected in bridge circuitrelationship, the bridge circuit connected to a source of pressurizedfluid, the resistance of said first variable resistor means preset to aselected resistance corresponding to the desired value of the monitoredparameter to obtain a balanced condition of the bridge circuit when themonitored parameter of the material passing in close proximity to and influid communication with said first sensing head is at the desired valuethereof, the bridge circuit developing a pressurized fluid signal duringthe unbalanced conditions of the bridge circuit when the value of themonitored parameter deviates from the desired value, said pair of fixedresistors having first ends thereof connected to a first juncture of thebridge circuit, the source of pressurized fluid connected to said firstjuncture, an input end of said at least one input fluid flow passage ofsaid first sensing head and a second end of a first of said pair offixed resistors connected to a second juncture of the bridge circuit,the output end means of said first sensing head comprising a first bodyhaving a cylindrical hollow interior providing a passage for theselected material being monitored by said fluidic gage, and said atleast one input fluid flow passage comprising a second hollow bodyhaving a threaded output end adapted for fluidtight connection with aradially formed threaded aperture in a sidewall of said first bodyspaced equally from the ends thereof to obtain fluid communication withthe hollow interior of said first body whereby pressurized fluidsupplied to the input end of said second hollow body from the secondjuncture of the bridge circuit issues into the hollow interior of saidfirst body and escapes through the ends thereof which form variableconstrictions formed by fixed dimensions of the ends of the hollowinterior and the variable diameter dimensions of the selected materialpassing therethrough, the variable constrictions forming variableresistances to fluid flow therethrough and causing the fluid pressure atthe second juncture of the bridge circuit to vary directly with thediameter of the monitored material, said second body due to the threadedconnection being readily interchangeable with like bodies of differentdiameter passages therethrough for operation at significantly differentinput pressures, for utilization with significantly different diametermaterials passing through said first body, and the like.
 7. The fluidicgage set forth in claim 6 wherein the output end means of said firstsensing head further comprises a pair of sharp-edged orifices mountedadjacent the ends of the hollow interior of said first body to therebyobtain a nonlaminar flow of the escaping pressurized fluid.
 8. Thefluidic gage set forth in claim 6 wherein the output end means of saidfirst sensing head further comprises a pair of threaded third bodiesadapted for fluidtight connection at like threaded ends of the hollowinterior of said first body and having narrow cylindrical passagestherethrough aligned with the hollow interior of said first body forproviding a passage for the material being monitored and thereby formingthe variable constrictions to the escaping pressurized fluid, said pairof third bodies being interchangeable with like bodies ofdifferent-diameter cylindrical passages therethrough for utilizationwith significAntly different-diameter materials passing therethrough. 9.The fluidic gage set forth in claim 8 wherein said pair of third bodiesare provided with beveled openings at the ends of the narrow cylindricalpassages which the monitored material first approaches.